I have a question about permanently attaching a flash hider. I know the ideal way is to have the device installed, drilled, pinned, then the end of the pin welded. I also read that the ATF is on with just welding the device and not pinning it. I can MIG weld, and am wondering, will a small tack weld from the MIG welder hurt the barrel? Will this satisfy the ATF? I'm trying to save some money, gunsmiths that I ask, want a lot to pin and weld.